Lubricated piston



Jan. 6, 1942.

C, J. COBERLY LUBRICATED PISTON Filed July l0, 1940 HA @f2/5E mec/f,)Cos TER a HAR/W5 Patented haii,

clarence J. calmly, Los Anreles, cam., assign'- v' or to RokoCorporation, Reno, Nev., a corporation of Nevada Application July 1o',1940, seriaiNo. 344,748

, (Cl. 30s- 6) 12 Claims.

This is a continuation-impart of my copending application Serial No.221,963, flied July 29,

1938, for Fluid operated pump, to which reference v is hereby made. n Aprimaryobject of my invention is to .provide a piston adapted toreciprocate in a cylinder in which a fluid is conveyed through thepiston to valve orice I1I therein. Secured to the valve` member IBI andprojecting upwardly in the the periphery thereof, including means forregulating the pressure at which such iiud is discharged tothe peripheryof the piston. I further prefer to utilize a regulating means such thatthe pressure of the fluid may be maintained below a predeterminedmaximum value.

A further object of the invention is to provide a novel type of pistonhaving means for lubricating the surface thereof during operation.

Other objects and advantages wllljbe apparent from the followingdescription and drawing, in which:

Fig. 1 is a'vertical sectional view of my invention.

Fig. 2 is a fragmentary sectional view taken on the line 2`r2 of Fig. 1.

Fig. 3 is a cross-sectional view takenson the line 3--6 of Fig. 1.

` In the drawing I show va piston |50 having a cylindrical body |5I,adapted to make a. sliding fit in a bore 93 of a cylinder liner 98, theexl .terior thereof being provided with annular chanlnels |52 receivingpiston rings |53 as is well known inthe art. 'Ihe cylindrical body I5!has an upper central bore |54 threadedly receiving the lower end of anupper piston rod I| having a longitudinal passage I therethrough, andhas a lower central bore |55 threadedly receiving the upper end of alower piston rod |32, the ends of the rodsbeing spaced apart by Vachamber |55. Oilset from the axis of the cylindrical body is a valvecylinder |51 which is` closed at its lower end by a lower plug |58 andhas at its upper end an upper plug |59 provided with a passage |60therethrough. Slidably disposed in the valve cylinder |51 is a regulatorvalve member |6| having a cup-shaped piston |62 within which acompression spring |63 is disposed so as to-engage both the piston andthe upper plug |50, and the valve member isV provided with a transverseopening |64 which registers with a port |65communicating betweenT theinterior of the valve cylinder |51 and the exterior of the cylindrical|5I. The cylindrical body |5`I is Vprvovided with a transverse opening|66 into which 'is threaded a transverse pin |61 having a. vertical uidpassage |68 communicating with a longitudinal iluid passage |66, one endof the transverse pin projecting into the transverse opening |64 of thevalve member I6| land having threaded thereon a tubular cap |10' havinga transverse opening |64is a conical valve element |12 adapted to seatin the lower end of the valve orifice |11 to close it, the valve memberbeing provided with a passage |13. Y

My piston is designed to permit a flow of operating iiuid underrelatively high pressure through the passage to the sliding surfaces ofthe piston and the liner 96 to lubricate them and to prevent1 foreignmaterials from lodging therebetween, which is broadly covered in myPatent No. 2,081,220, issued May 25, 1937, the

present construction being an improvement thereon. My invention is ofparticular utility in connection with a deep well pump. In a deep wellinstallation, such as, `for example, alwell 6500 feet deep, the pressureof the operating fluid maybe as high as 4000 pounds per square inch,whereas in using the piston' I 50 in the pump shown in' my abovereferred to application Serial No. 221,963, the fluid load on the piston|50 may only be 400 pounds per square inch. Obviously'. if operatingfluid under a high pressure, such as 4000 pounds per square inch, isconveyed to the outer surface of the piston, it will either causeexcessive leakage lengthwise of the piston or will require anexcessive'functional duty to be imposed on the piston rings |53.Consequently. a principal object of my piston design is to provide apressure reducing means for reducing the pressure of the operating uidto a value approximating the uid load on the piston |50.

In operation, operating fluid under pressure is at all times in thelongitudinal'passage I of theupper piston rod ||0 and in the axialpassage |35 of thelower piston rod |32, communication therebetween beingafforded through thechamber |56 ofthe piston |50. The operating fluidows through the vertical and longitudinal iluid passages |66 and |69,through vthe'tubular cap |10, and through the orifice |1| into thetransverse opening |64.- 'Ihe spring |63 normally exerts a downwardforce on the valve member |6I, tending to hold it in open position inwhich the valve element |12 is out of seating engagement with the valveorifice |1|. Operating :duid -then r passes through the passage |13into'the lower end of the valve cylinder |51, and exerts an upward forceon thevalve member |6I tending to move the valve member upwardly againsttheaction ofA in the the spring |63. and any fluid pressure spring |63lis set to resist movement of the valve' member |6| until the pressureof the operating iluid rises above a predetermined maximum, such as 500pounds per square inch. Thus, if the normal pressure on the operatinguid is 4000 pounds per square inch, the excess pressure in the valvecylinder |51 below the valve member will move the valve member |6|upwardly until thevalve ing means in the une of said 'passage meansadapted to maintain the pressure of iluid passing therethrough belowapredetermined maximum regardless of the pressure of iluid at saidSource.

4. Ina piston device, the combination of; a

piston adapted to be slidably received in a cylinder, said piston havinga central chamber, passage means communicating between said chamber andthe periphery of said piston, and a bore therein offset from saidcentral chamber; a piston rod connected to said piston and having alongitudinal passage therethrough communicating with said centralchamber, the other end of said passage being adapted to be connected "toa ysource of fluid under pressure; a valve member element |12 issuiiiciently closed so that the spring |63 will balance the pressure ofthe :fluid in the valve cylinder.y It will thus be understood that thisconstruction operates as a regulator to maintain the pressure ofoperating fluid owing outwardly through the transverse opening |64 andthe port |65 below a predetermined maximum, thuspreventlng excessiveleakage of operating iiuld lengthwise of the piston |50, and permittingthe use of relatively light frictional contact of the piston rings |53with the bore 93 of the liner 98.` It will also be understood that thispiston construction may be used to advantage in other devices, and I donot intend to be limited to its use in connection with a fluid operatedpump. Although I have hereinshown and described a simple and practicalembodiment of my invention, I do not intend to be limited to the detailsof construction disclosed but intend my invention to be accorded thefull scope of the following claims.

I claim as my invention: Y

1. In a piston device, the combination of: piston means adapted to beslidablyureceived in a movable in said bore to regulate the flow oi'fluid through said passage; and means in said bore for controlling themovement oi' said valve member to maintain the tluid dischargedvfthrough said passage to the periphery of said piston below apredetermined maximum pressure.

5. In a piston device, the combination of: a'

piston adapted to be slidably received in a cylinder, said piston havinga central chamber, passage means communicating between said chamber andthe periphery of said piston, and a bore therein oil'st from saidcentral chamber; a piston rod connected to said piston and having alongitudinal passage therethrough communicating with said centralchamber, the'other end of said passage being adapted to be connected toa source of fluid .under pressure; a tubular valve member movable insaid bore to regulate the ow of fluid through said passage; and means insaid bore for controllingk the movement of said valve member to maintainthe fluid discharged through said passage to the periphery of saidpiston below .a predetermined maximum pressure, said means including aspring engaging said tubular valve a member and means for adjusting thetensionof said spring.

cylinder; walls forming a passage for conveying a iluid through saidpistonmeans to the periphery thereof, said passage also communicating'with a source of iluid under relatively high pressure; and pressureregulating means in the line of said passage adapted to regulate thedischarge of fluid therethrough to the periphery of said piston means ata predetermined pressure regardless ofthe pressure of iiuid in saidsource of supply.

2. In a pistondevice, the combination of: pis- 6. In a piston device,the combination of piston means adapted to be slidably received in acylinder, said piston means having a central chamber and passage meanscommunicating bey tween said central'chamber and the outer peton meansadapted to be slidably received in a cylinder;- walls forming a passagefor conveying a iluid through said piston means to the peripherythereof, said passage also communicating with a source of iuidunderrelatively high pressure; and pressure regulating means in the line ofsaid passage adapted to maintain the pressure of uid dischargedoutwardly from said passage to the periphery of said piston 'means belowa sure of fluid at said source.

3. In a piston device', the combination of: pisl ton means adapted to beslidably received in a riphery of said piston means; piston rod meansconnected to said piston means and having a fluid passage thereincommunicating with said central chamber, the other end of said uidpassage being connected to a `source of fluid under pressure; a meteringvalve in the line of said passage means and adapted to meter a flow offluid through said passage means; and means for operating said meteringvalve in response to iluid pressure in said central cliamberto maintaina uid flow through said lpassage means below a predetermined maximum.

'1. In a piston device,' the combination of: a`

piston adapted to be slidably received in acylinder, said piston havinga central chamber and passage means communicating between said centralchamber and the outer periphery of said piston, there being an offsetborel provided in said f piston parallel'with but oiset from the axis ofconnected to said piston means and having 'a fluid passage thereincommunicating with said central chamber, the other end of said uid pasfsage being connected to a source of -fluid undervrelatively,'highpressure; and pressure regulat-- said piston; a piston rod connected tosaid piston and having a piston 'rod passage therein communicatingbetween said central chamber and a source of supply of uid underpressure; a tubular metering valve in said offset bore and movable tocontrol a iow o1' fluid through said passage means; a valve membercarriedby said tubular metering valve and adapted to close said passagemeans; and means for normally yieldably maintaining said tubularmetering valve in a position in which said valve member opens saidpassage, but movable to close said valve member in response to a rise influid press'ure in said passage means.

8. In a piston device, the combination of piston means adapted to beslidably received in a cylinder; walls forming a passage for conveying afluid through said piston means to the periphery thereof, said passagealso communicating with a source of fluid under pressure; valve means inthe line of said passage and movable to control the iiow of fluidtherethrough from said source to said periphery; retaining meansoperatively connected to said valve means and adapted to maintain saidvalve means open when the uid pressure in said passage is below apredetermined maximum; and closure means operatively connected to saidvalve means for f moving said valve means toward closed position againstthe action of saidA retaining means so as to throttle said flow when thefluid pressure in said passage exceeds said predetermined maximum. A

9. In' a. piston device, the combinationof: piston means adapted to beslidably received in a. cylinderwalls forming a passage for conveying afluid through said piston means to the periphery thereof, 'said passagealso communicating with a source of uid under pressure;

valve means in the line of said passage and movable to control the iiowfof iiuid therethrough from said source to said periphery; .retainingmeans operatively connected to said valve means and adapted to maintainsaid valve means open when the fluid pressure in said passage is below apredeterminedmaximum; closure means of iiuid supplv communicating with'mid passage; a valve member in the line ofvsaid passage and movablebetween open and closed `position to throttle a iiow of fluid throughsaid passage; retaining means for normally retaining said valve memberin said open position when the pressure of iiuid in said passage remainsbelow a predeoperatively connected to said valve means for moving saidvalve means toward closed position against the action of said retainingmeans so as to throttle said iiow when the fluid pressure in saidpassage exceeds said predetermined maximimi; andmeans for adjusting thepredetermined maximum pressure at which said closure means will movesaid valve means toward closed position.

10. In combination: walls forming a passage adapted to convey fluidunder pressure; a source termined maximum; and closure means operatingin response to a rise in pressure of said fluid in said passage abovesaid predetermined maximum to move said valve member toward said closedposition. y l1. In combination: walls forming a passage adapted toconvey uid under pressure; ya source fluid in said passage above saidpredetermined maximum to move said valve member toward said closedposition against the action of said Spring.

1 2. In combination: -walls forming a passage l adapted to convey uidunder pressure, said passage having an inlet end and a discharge end; asource of uid supply communicating with said inlet end of said passage;a -valve member in said passage between said inlet and discharge f 'endsand movable between open and closed po- .sitions to throttle a flow ofuid through said passage; means fornormally retaining said valve memberinopen position so long as the fluid pressure inthe `discharge end ofsaid passage remains below a predetermined maximum; and

, means loperating in response to a rise in uid pressure in said passageabove said predetermined maximum to move said Avalve member toward' saidclosedv position to throttle the flow of uid therethroughI so as, tomaintain the fluid pressure in said discharge end of said passage belowa predetermined value.

CLARENCE J. COBERLY.

